[原]C++实现ROL与ROR

 

//ROL

template<typename T>
T CPP_ROL(T n, const int bitN)
{
 const int BITLEN = sizeof(T)*8;
 n = (n >> (BITLEN-bitN)) | (n << bitN);
 return n;
}
/***************************

ROR与上面基本相同,n = (n << (BITLEN-bitN)) | (n >> bitN); 

*****************************/
#include <iostream>
using namespace std;
int main()
{
 int n = 1, bitN = 16;
 cout << hex << n << "\n";
 n = CPP_ROL(n, bitN);
 cout << hex << n;
    return 0;
}